It used to be so simple. One would receive their daily milk bottles from the milkman. Nowadays, the number of milk alternatives is enough to make anyone’s head swirl. There is skim milk, organic milk, fortified milk, raw milk, low-fat milk, buttermilk, A2 milk, lactose-free milk, flavored milk, condensed milk, powdered milk, evaporated milk, scalded milk, and now protein milk.
There is a common baseline process that all milk variants go through. First, once the milk is obtained from the cow, which is the raw milk, it has to undergo a pasteurization process at a processing plant. In this step, the milk is heated to 72°C for 15 seconds to kill off any harmful bacteria. During the pasteurization process, you often get milk fat particles. Therefore, the next step is to homogenize the milk so that it has the smooth texture we are all familiar with. This is done by passing the milk through small holes at high pressures to break down the milk fat particles. Once these are broken down, the milk can be cooled down to 4°C. The high temperature used for processing up to this point causes many nutrients of milk such as fat-soluble vitamins A and D and calcium to be lost. Therefore, most countries require dairy industries to put milk products through a fortification process that adds back these essential nutrients. These are typically added back in the form of powdered vitamins and minerals. Once these basic steps are completed, producers can generate several different milk alternatives. Some refer to these as “designer milk” products.
The most recent milk variant is a protein milk that has a higher amount of protein than regular milk. This might draw the attention of anyone trying to get more “gains” at the gym. In contrast to protein shakes, high-protein milk, otherwise known as ultra-filtered milk, does not have an increased protein content due to the addition of protein powder. Rather, it is produced through an ultrafiltration process. In the ultrafiltration process, the regular whole milk is passed through various semi-permeable membranes which act as filters that separate milk components based on their molecular weights. This means that the low molecular weight components of milk such as lactose, minerals, and water can be separated from the high molecular weight components such as milk proteins. Once all the components are separated, the dairy industry can decide which components to add more or less of. In the context of high-protein milk, they often choose to add more milk proteins. This results in 18 grams of protein per serving of ultra-filtered milk in comparison to the typical 8 grams of protein in regular milk. In addition, this “designer milk” often also contains 50% less sugar and more calcium than regular milk. Furthermore, since the ultra-filtration process removes most of the lactose, brands such as Fairlife have chosen to add lactase enzyme to also make the milk completely lactose-free.
We were all told growing up that we needed milk to grow strong, but do we really need high-protein milk? There is no doubt that protein has become a major player in the health and wellness industry. It seems that most companies and influencers are encouraging consumers to increase their protein intake. However, while protein is certainly an important nutrient in our diets, most people consume the recommended 0.8 grams per kilogram of weight in a normal day of eating.
People who are worried about protein intake, especially high-performing athletes, typically turn to protein powders. However, as with many supplements, the science on the benefits and safety of protein powder is not quite clear; some claims certainly have more support than others. For example, it has been suggested that protein powders may not necessarily be ideal for muscle building due to protein spiking; while this is possible, it does not necessarily pose a health risk.
On the other hand, some individuals have raised concerns about the safety of protein powders. In the United States, since protein powder is a dietary supplement, the FDA leaves it up to the manufacturers to determine the efficacy and safety of the product. This has prompted independent investigations into the safety of protein powders. One such study was conducted by the Clean Label Project. They screened 134 protein powder products and found 130 types of toxins among these products; these toxins included heavy metals such as lead, arsenic, cadmium, and mercury, bisphenol-A(BPA), pesticides, and PFAS. However, the reliability of these findings is unclear. The results from the Clean Label Project have not yet been replicated or peer-reviewed.
Furthermore, the original reports are not available for public access. Therefore, while these “contaminants” were detected in some unidentified protein powders, the levels at which they are present are not specified by the Clean Label Project. This makes the consequences of the findings to human health unknown as it is possible these contaminants are present below federal guidelines. In Canada, protein powders are considered Natural Health Products (NHP) and are subject to more monitoring. Health Canada tests certain NHPs for heavy metal contaminants; those with levels above the allowed limit are not sold or are altered to meet the guidelines.
Since the long-term effects of supplementing with protein powder have yet to be determined, ultra-filtered milk may be an attractive option for individuals with low-protein intake or high-endurance athletes looking to increase their protein intake in a “cleaner” manner. However, most individuals don’t require this extra protein source and would not benefit from spending the extra money on “designer” milk.
Although we no longer receive our daily milk bottles from the milkman, we can take comfort in knowing that the decision of which milk we consume – if any – is up to us. However, with this power of choice comes the responsibility to understand the different products on the market and make conscious choices for our personal health.
Editor’s Note: This article was updated on June 21st, 2024.
Daniela is a recent B.Sc. graduate from the program of Physiology at McGill. She is very passionate about understanding the human body and how we can all individually adapt our daily lifestyles to improve its functioning.
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